I have a UITableView, and I want to attach a UIPanGestureRecognizer to each of the cells, which are subclassed UITableViewCells - ArticleCells. In the awakeFromNib method I add the pan gesture recognizer, but it never fires. Why?
- (void)awakeFromNib {
[super awakeFromNib];
self.cellBack = [[CellBack alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, 80)];
[self.contentView addSubview:self.cellBack];
self.cellFront = [[CellFront alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, 80)];
[self.contentView addSubview:self.cellFront];
UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(pannedCell:)];
panGestureRecognizer.delegate = self;
}
Which should be firing this method. But I put a breakpoint on it and it never does get fired.
- (void)pannedCell:(UIPanGestureRecognizer *)recognizer {
if (recognizer.state == UIGestureRecognizerStateBegan) {
_firstTouchPoint = [recognizer translationInView:self];
NSLog(#"fired");
}
else if (recognizer.state == UIGestureRecognizerStateChanged) {
NSLog(#"fired");
CGPoint touchPoint = [recognizer translationInView:self];
// Holds the value of how far away from the first touch the finger has moved
CGFloat xPos;
// If the first touch point is left of the current point, it means the user is moving their finger right and the cell must move right
if (_firstTouchPoint.x < touchPoint.x) {
xPos = touchPoint.x - _firstTouchPoint.x;
if (xPos <= 0) {
xPos = 0;
}
}
else {
xPos = -(_firstTouchPoint.x - touchPoint.x);
if (xPos >= 0) {
xPos = 0;
}
}
if (xPos > 10 || xPos < -10) {
// Change our cellFront's origin to the xPos we defined
CGRect frame = self.cellFront.frame;
frame.origin = CGPointMake(xPos, 0);
self.cellFront.frame = frame;
}
}
else if (recognizer.state == UIGestureRecognizerStateEnded) {
[self springBack];
}
else if (recognizer.state == UIGestureRecognizerStateCancelled) {
[self springBack];
}
}
And in the .h file I added so it would be notified as implementing it. But it never calls it as I said.
Why?
Did you do this?
[self.contentView addGestureRecognizer:panGestureRecognizer];
Related
I am trying to make a UIView open & close on Swipe/Pan Gesture & i found some help from following link
Link , it's close to what i m trying to make.
I want UIView to be open by 100 pixels default & User can swipe/pan the UIView using gesture till 75% of the parent UIViewController & back to 100 pixels but it's flicking in this below code. I want UIView's X position to be 0 so it can be like a drawer opening from top.
- (void)viewDidLoad {
[super viewDidLoad];
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(move:)];
drawerView = [self.storyboard instantiateViewControllerWithIdentifier:#"drawerVC"];
[drawerView.view setFrame:CGRectMake(0, -self.view.frame.size.height + 100, self.view.frame.size.width, self.view.frame.size.height * 0.75)];
[drawerView.view setBackgroundColor:[UIColor redColor]];
[drawerView.view addGestureRecognizer:panGesture];
}
-(void)move:(UIPanGestureRecognizer*)recognizer {
recognizer.view.center = CGPointMake(self.view.frame.size.width/2,
recognizer.view.center.y + translation.y);
[recognizer setTranslation:CGPointMake(0, 0) inView:self.view];
if (recognizer.state == UIGestureRecognizerStateEnded) {
CGFloat magnitude = sqrtf((velocity.x * velocity.x) + (velocity.y * velocity.y));
CGFloat slideMult = magnitude / 200;
NSLog(#"magnitude: %f, slideMult: %f", magnitude, slideMult);
float slideFactor = 0.1 * slideMult; // Increase for more of a slide
CGPoint finalPoint = CGPointMake(0,
recognizer.view.center.y + (velocity.y * slideFactor));
finalPoint.x = 0;
finalPoint.y = MIN(MAX(finalPoint.y, 0), drawerView.view.frame.size.height*.75);
if (fabs(recognizer.view.frame.origin.y) >= fabs(yOffset))
{
return;
}
NSLog(#"ended %f",finalPoint.y);
if (finalPoint.y < recognizer.view.frame.size.height/2) {
// [self movePanelToOriginalPosition];
}
else{
[self movePanelToCenterPosition];
}
}
}
-(void)movePanelToCenterPosition {
[UIView animateWithDuration:0.3 delay:0 options:UIViewAnimationOptionCurveEaseIn animations:^{
drawerView.view.frame = CGRectMake(0, 0, drawerView.view.frame.size.width, drawerView.view.frame.size.height);
}
completion:^(BOOL finished) {
// Stuff to do
}];
}
Is there anything that can prevent user to pan UIView in Top(Up) direction if UIView is at default(100 pixels) & can only swipe down to desired CGPoint.
In your move: method you check if the move start or is in progress
else if (recognizer.state == UIGestureRecognizerStateBegin || recognizer.state == UIGestureRecognizerStateChanged)" and in the if view is at its limit. if so you can disabled/reenabled the gesture recognizer. This will cancel the pan...
- (void) move:(UIGestureRecognizer *)sender
{
if(sender.state == UIGestureRecognizerStateBegan || sender.state == UIGestureRecognizerStateChanged)
{
BOOL shouldEnablePan = NO; // TODO: do some logic here to figure out if you want to allow pan
if(!shouldEnablePan && [sender isKindOfClass:[UIPanGestureRecognizer class]])
{
sender.enabled = NO;
sender.enabled = YES;
}
} else ...
}
Using a UIPanGestureRecognizer in my view controller, I'm trying to draw a view (ArrowView) at an angle based upon the touch location. I'm trying to use CGAffineTransformRotate to rotate the view based up the angle between the first touch and the current touch, but this isn't working unless the view has already been drawn by at lease 20 or more pixels. Also, when drawing, the view doesn't always line up under my finger. Is this the correct approach for this situation? If not, does anyone recommend a better way of accomplishing this? If so, what am I doing wrong?
ViewController.m
#implementation ViewController {
ArrowView *_selectedArrowView;
UIColor *_selectedColor;
CGFloat _selectedWeight;
CGPoint _startPoint;
}
- (void)viewDidLoad {
[super viewDidLoad];
_selectedColor = [UIColor yellowColor];
_selectedWeight = 3;
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(panHandler:)];
[self.view addGestureRecognizer:pan];
}
- (void) panHandler: (UIPanGestureRecognizer *) sender {
if (sender.state == UIGestureRecognizerStateBegan) {
//Instantiate the arrow
CGPoint touchPoint = [sender locationInView:sender.view];
_startPoint = touchPoint;
_selectedArrowView = [[ArrowView alloc] initWithFrame:CGRectMake(touchPoint.x, touchPoint.y, 0, 25) withColor:_selectedColor withWeight:_selectedWeight];
_selectedArrowView.delegate = self;
[self.view addSubview:_selectedArrowView];
[self.view bringSubviewToFront:_selectedArrowView];
} else if (sender.state == UIGestureRecognizerStateChanged) {
//"Draw" the arrow based upon finger postion
CGPoint touchPoint = [sender locationInView:sender.view];
[_selectedArrowView drawArrow:_startPoint to:touchPoint];
}
}
#end
ArrowView.m
- (void) drawArrow: (CGPoint) startPoint to: (CGPoint) endPoint {
startPoint = [self convertPoint:startPoint fromView:self.superview];
endPoint = [self convertPoint:endPoint fromView:self.superview];
if (_initialAngle == -1000 /*Initially set to an arbitrary value so I know when the draw began*/) {
_initialAngle = atan2(startPoint.y - endPoint.y, startPoint.x - endPoint.x);
[self setPosition:0];
} else {
CGFloat ang = atan2(startPoint.y - endPoint.y, startPoint.x - endPoint.x);
ang -= _initialAngle;
self.transform = CGAffineTransformRotate(self.transform, ang);
CGFloat diff = (endPoint.x - self.bounds.size.width);
NSLog(#"\n\n diff: %f \n\n", diff);
self.bounds = CGRectMake(0, 0, self.bounds.size.width + diff, self.bounds.size.height);
_endPoint = CGPointMake(self.bounds.size.width, self.bounds.size.height);
[self setNeedsDisplay];
}
}
- (void) setPosition: (CGFloat) anchorPointX {
CGPoint layerLoc;
if (anchorPointX == 0) {
layerLoc = CGPointMake(self.layer.bounds.origin.x, self.layer.bounds.origin.y + (self.layer.bounds.size.height / 2));
} else {
layerLoc = CGPointMake(self.layer.bounds.origin.x + self.layer.bounds.size.width, self.layer.bounds.origin.y + (self.layer.bounds.size.height / 2));
}
CGPoint superLoc = [self convertPoint:layerLoc toView:self.superview];
self.layer.anchorPoint = CGPointMake(anchorPointX, 0.5);
self.layer.position = superLoc;
}
- (CGFloat) pToA: (CGPoint) touchPoint {
CGPoint start;
if (_dotButtonIndex == kDotButtonFirst) {
start = CGPointMake(CGRectGetMaxX(self.bounds), CGRectGetMaxY(self.bounds));
} else {
start = CGPointMake(CGRectGetMinX(self.bounds), CGRectGetMinY(self.bounds));
}
return atan2(start.y - touchPoint.y, start.x - touchPoint.x);
}
Link to project on GitHub: Project Link
Figured it out.
I had to make it have an initial width so the angle would work.
_initialAngle = atan2(startPoint.y - endPoint.y, startPoint.x - (endPoint.x + self.frame.size.width));
Now i develop an app that all user drag, rotate and scale image inside uiview. but when i want to save image view data like rotate value and scale value. i found scale value from [[img.layer valueForKeyPath:#"transform.scale"] floatValue] diff with scale that i found. the scale value is like below.
-(void)scale:(id)sender {
if([(UIPinchGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {
_lastScale = 1.0;
}
CGFloat scale = 1.0 - (_lastScale - [(UIPinchGestureRecognizer*)sender scale]);
//CGFloat scale = 1.0 + ([(UIPinchGestureRecognizer *)sender scale] - _lastScale);
CGAffineTransform currentTransform = self.transform;
CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);
[self setTransform:newTransform];
_lastScale = [(UIPinchGestureRecognizer*)sender scale];
CGFloat size = [[self.layer valueForKeyPath:#"transform.scale"] floatValue];
self.saveScale = _lastScale;
NSLog(#"Scale %f %f",_lastScale, size);
}
so the save scale value is diff with [[img.layer valueForKeyPath:#"transform.scale"].
PLEASE HELP!!!
Declare Variable -> CGFloat currentScale;
- (void) handlePinches:(UIPinchGestureRecognizer*)paramSender{
if (paramSender.state == UIGestureRecognizerStateEnded){
currentScale = paramSender.scale;
} else if (paramSender.state == UIGestureRecognizerStateBegan &&
self.currentScale != 0.0f){
paramSender.scale = currentScale;
}
if (paramSender.scale != NAN &&
paramSender.scale != 0.0){
paramSender.view.transform =
CGAffineTransformMakeScale(paramSender.scale,
paramSender.scale);
}
}
try this
You need to add Delegate
#interface MyClass : MySuperClass <UIGestureRecognizerDelegate>
- (void)viewDidLoad
{
[super viewDidLoad];
// set up the image view
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"someImage"]];
[imageView setBounds:CGRectMake(0.0, 0.0, 120.0, 120.0)];
[imageView setCenter:self.view.center];
[imageView setUserInteractionEnabled:YES]; // <--- This is very important
// create and configure the pinch gesture
UIPinchGestureRecognizer *pinchGestureRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(pinchGestureDetected:)];
[pinchGestureRecognizer setDelegate:self];
[imageView addGestureRecognizer:pinchGestureRecognizer];
// create and configure the rotation gesture
UIRotationGestureRecognizer *rotationGestureRecognizer = [[UIRotationGestureRecognizer alloc] initWithTarget:self action:#selector(rotationGestureDetected:)];
[rotationGestureRecognizer setDelegate:self];
[imageView addGestureRecognizer:rotationGestureRecognizer];
[self.view addSubview:imageView]; // add the image view as a subview of the view controllers view
}
add this two methods
- (void)pinchGestureDetected:(UIPinchGestureRecognizer *)recognizer
{
UIGestureRecognizerState state = [recognizer state];
if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
{
CGFloat scale = [recognizer scale];
[recognizer.view setTransform:CGAffineTransformScale(recognizer.view.transform, scale, scale)];
[recognizer setScale:1.0];
}
}
- (void)rotationGestureDetected:(UIRotationGestureRecognizer *)recognizer
{
UIGestureRecognizerState state = [recognizer state];
if (state == UIGestureRecognizerStateBegan || state == UIGestureRecognizerStateChanged)
{
CGFloat rotation = [recognizer rotation];
[recognizer.view setTransform:CGAffineTransformRotate(recognizer.view.transform, rotation)];
[recognizer setRotation:0];
}
}
after add this delegate method
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
you can handle also pangesture using this method.
add pan gesture in to image.
self.panResizeGesture = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(handlePanGestures:)];
imgPatSelect.userInteractionEnabled = YES;
[imgPatSelect addGestureRecognizer:self.panResizeGesture];
add this method to handle pan.
- (void) handlePanGestures:(UIPanGestureRecognizer*)recognizer{
CGPoint translation = [recognizer translationInView:self.view];
CGRect recognizerFrame = recognizer.view.frame;
recognizerFrame.origin.x += translation.x;
recognizerFrame.origin.y += translation.y;
// Check if UIImageView is completely inside its superView
if (CGRectContainsRect(self.view.bounds, recognizerFrame)) {
recognizer.view.frame = recognizerFrame;
}
// Else check if UIImageView is vertically and/or horizontally outside of its
// superView. If yes, then set UImageView's frame accordingly.
// This is required so that when user pans rapidly then it provides smooth translation.
else {
// Check vertically
if (recognizerFrame.origin.y < self.view.bounds.origin.y) {
recognizerFrame.origin.y = 0;
}
else if (recognizerFrame.origin.y + recognizerFrame.size.height > self.view.bounds.size.height) {
recognizerFrame.origin.y = self.view.bounds.size.height - recognizerFrame.size.height;
}
// Check horizantally
if (recognizerFrame.origin.x < self.view.bounds.origin.x) {
recognizerFrame.origin.x = 0;
}
else if (recognizerFrame.origin.x + recognizerFrame.size.width > self.view.bounds.size.width) {
recognizerFrame.origin.x = self.view.bounds.size.width - recognizerFrame.size.width;
}
}
// Reset translation so that on next pan recognition
// we get correct translation value
[recognizer setTranslation:CGPointMake(0, 0) inView:self.view];
}
I am having trouble using initWithItem:attachedToItem: Initializes an attachment behavior that connects the center point of a dynamic item to the center point of another dynamic item.
But when I changed the center point of topview using method pan,only the topview moved around,I can't get the other view to move.Isn't it should be moving together?
(BTW I am trying to implement a pile of cards and move around all together when I pan the card in the top.)
-(void)pinch:(UIPinchGestureRecognizer *)gesture
{
if(gesture.state == UIGestureRecognizerStateChanged){
CGPoint pinchCen = [gesture locationInView:self.cardArea];
if (gesture.scale <= 0.5 && !self.pileStat) {
self.pileStat = !self.pileStat;
NSUInteger number = [self.cardViews count];
UIView *topView = [self.cardViews lastObject];
[topView addGestureRecognizer:[[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(pan:)]];
for (int i = 0; i < number;i++) {
UIView *cardView = self.cardViews[i];
[UIView animateWithDuration:0.5 animations:^{cardView.center = CGPointMake(pinchCen.x+i%10*0.5, pinchCen.y+i%10*0.5);} completion:^(BOOL finished){
if(i != number - 1){
UIAttachmentBehavior *attach = [[UIAttachmentBehavior alloc]initWithItem:cardView attachedToItem:topView];
[self.animator addBehavior:attach];
}
}];
}
}
else if(gesture.scale > 1.5 && self.pileStat)
{
self.pileStat = !self.pileStat;
}
}else if (gesture.state == UIGestureRecognizerStateEnded){
gesture.scale = 1.0f;
}
}
-(void)pan:(UIPanGestureRecognizer *)gesture
{
if (gesture.state == UIGestureRecognizerStateChanged || UIGestureRecognizerStateEnded) {
UIView *topView = [self.cardViews lastObject];
CGPoint trans = [gesture translationInView:self.cardArea];
topView.center = CGPointMake(trans.x+topView.center.x, trans.y+topView.center.y);
[gesture setTranslation:CGPointMake(0, 0) inView:self.cardArea];
}
}
setCenter does not play nice with UIDynamicAnimator. Instead of changing the center coordinate of your top view, you should use another UIAttachmentBehavior that you attach to your touch. Replace your pan gesture handler with this method:
//Add a variable in your interface or header section called "touchAttachment" of type UIAttachmentBehavior
- (void) pan: (UIPanGestureRecognizer *) sender{
UIView* topCard = [self.cardViews lastObject];
if (sender.state == UIGestureRecognizerStateBegan){
_touchAttachment = [[UIAttachmentBehavior alloc] initWithItem:topCard
attachedToAnchor: [sender locationInView:self.view]];
[self.animator addBehavior:_touchAttachment];
}
else if (sender.state == UIGestureRecognizerStateChanged){
[_touchAttachment setAnchorPoint: [sender locationInView: self.view]];
}
else if (sender.state == UIGestureRecognizerStateEnded){
[self.animator removeBehavior: _touchAttachment];
_touchAttachment = nil;
}
}
Make sure you add the "touchAttachment" variable.
Hope it helps :)
I am adding UIPanGestureRecogniser to drag and drop images in a view.I want to drag only one image at a time.but I am able to drag two images at a time.which should not happen.
I am stuck with this bug since morning.I tried all the ways i found on google.
- (void)viewDidLoad
{
[super viewDidLoad];
[self.view setMultipleTouchEnabled:NO];
for(UIImageView *iView in self.movableArray){
if ([iView isMemberOfClass:[UIImageView class]]){
UIPanGestureRecognizer * recognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handlePan:)];
[iView addGestureRecognizer:recognizer];
[iView setUserInteractionEnabled:YES];
recognizer.delegate = self;
}
}
}
- (IBAction)handlePan:(UIPanGestureRecognizer *)recognizer {
[gameView bringSubviewToFront:[(UIPanGestureRecognizer *)recognizer view]];
CGPoint translation = [recognizer translationInView:gameView];
recognizer.view.center = CGPointMake(recognizer.view.center.x + translation.x,
recognizer.view.center.y + translation.y);
[recognizer setTranslation:CGPointMake(0, 0) inView:gameView];
self.dragObjectImageView = (UIImageView*)recognizer.view;
if(recognizer.state == UIGestureRecognizerStateBegan){
int ind = [self.movableArray indexOfObject:self.dragObjectImageView];
for(int i = 0 ; i < [self.movableArray count] ; i ++){
if( i != ind ){
[[self.movableArray objectAtIndex:i] removeGestureRecognizer:recognizer];
}
}
self.homePosition = self.dragObjectImageView.frame;
}
if (recognizer.state == UIGestureRecognizerStateEnded) {
CGPoint touchPoint = [recognizer locationInView:gameView];
for (UIImageView *iView in self.staticArray) {
if ([iView isMemberOfClass:[UIImageView class]]) {
if (touchPoint.x > iView.frame.origin.x &&
touchPoint.x < iView.frame.origin.x + iView.frame.size.width &&
touchPoint.y > iView.frame.origin.y &&
touchPoint.y < iView.frame.origin.y + iView.frame.size.height)
{
self.dropTargetImageView = iView;
}
}
}
if(self.dragObjectImageView.tag == self.dropTargetImageView.tag){
self.dragObjectImageView.frame = CGRectMake(self.dropTargetImageView.frame.origin.x, self.dropTargetImageView.frame.origin.y + self.dropTargetImageView.frame.size.height/2 - 15, self.dragObjectImageView.frame.size.width, self.dragObjectImageView.frame.size.height);
[self.dragObjectImageView removeGestureRecognizer:recognizer];
}
}else{
self.dragObjectImageView.frame = self.homePosition;
}
}
}
This happens because you are adding one UIPanGestureRecognizer for each of your imageViews. Try adding only one to your self.view (and have your imageViews to setUserInteractionEnabled:NO, otherwise they will trap the touch). Also put
recognizer.maximumNumberOfTouches = 1;
Before you add it to your view. All you have to do now is to test which image view should be dragged in your handlePan method. You should check the recognizer state and when it turns to UIGestureRecognizerStateBegan you should save which imageView is being dragged. Then as the state is UIGestureRecognizerStateChanged just drag the view around. The most general way you can find out which view was touched (as i don't know your full view hierarchy) would be to do something like:
NSUInteger index = [self.movableArray indexOfObjectPassingTest:(BOOL (^)(id obj, NSUInteger idx, BOOL *stop)){
UIView* hitTest = (UIView*)obj;
return [hitTest pointInside:firstTouch withEvent:nil];
}];
if ( index != NSNotFound )
self.draggingView = self.moveableArray[index];
else
self.draggingView = nil;
Then of course if self.draggingView is nil you would do nothing when the user is panning around.
You should create a mechanism to setUserInteractionEnable = NO when your
- (IBAction)handlePan:(UIPanGestureRecognizer *)recognizer;
Is called on the other images. You can either do that, or disable the others UIPanGestureRecognizer, like: myPanGestureRecognizer.enabled = NO;
A quick example:
- (IBAction)handlePan:(UIPanGestureRecognizer *)recognizer
{
UIImageView *currentDraggedImageView = recognizer.view;
// Based on this, you can iterate again on your UIImageViews and disable them.
// Once your work is done with gesture recogniser, you can re-enable them.
}